Cobalt ferrite/MIL-101(Fe)/graphene oxide heterostructures coupled with peroxymonosulfate for triclosan degradation

Abstract

Sulfate radical-based-advanced oxidation processes (SR-AOPs) have been recently considered for micropollutants degradation in water treatment. In the present study, cobalt ferrite (CoFe2O4), a metal-organic framework (MOFs) (MIL-101(Fe)), and graphene oxide (GO) were used to synthesize a novel heterostructure, CoFe2O4/MIL-101(Fe)/GO (C/M/G), through a hydrothermal method. The structural properties of C/M/G were determined by several characterization methods. The samples tested in the degradation of triclosan (TCS) with perox-ymonosulfate (PMS), were able to activate it generating the highly active hydroxyl (HO center dot) and sulfate radicals (SO4 center dot-). The effect and interaction of controlling parameters on TCS removal were investigated. Complete removal of TCS (500 mu g/L) was achieved with pH 5, 0.04 g/L catalyst, and 8 mu M PMS in only 30 min. The TCS removal declined obviously in the presence of radical scavengers and coexisting ions. The leachings of cobalt (Co) and iron (Fe) ions were lower than those of other CoFe2O4 composites coupled with PMS. Moreover, this process demonstrated high performance in the treatment of TCS in tap and well water. Accordingly, the C/M/G/ PMS system seems to be a highly effective and environmentally compatible process for micropollutant degra-dation in water treatment.